Inspection device



25, 1936. G. J. HEWLETT 0 ,9 v

INSPECTION DEVICE Filed June 11, 1934 I ZSheets-Sheet 1 INVENTOK 660966 J flnvzzrr A TTORNE Y Patented Aug. 25, 1936 PATENT orlucr.

, 2,051,946 msrncrronbnvrcs George J, Hewlett, Parma Heights, on Application June 11,1934, Serial No. 130.03:

: UNITED STATES This invention relates to inspection devices for use in visually inspecting articles in the process of, or after the completion of manufacture. This invention particularly relates to that class oi. inspection devices in which an enlarged image of the article is formed to aid the observer to detect certain characteristics or defects in the articles inspected. More specifically, this invention relates to the devicesorthis class in which the articles inspected are mechanically conveyed thru the field of the inspection device and in which enlarged images of the articles inspected are automatically and progressively produced. The specific embodiment of this invention disclosed herein is its adaptation as a bottle inspection device particularly devised for use in inspecting bottled liquids such as beverages, chemicals, foods, and other transparent and partially transparent or translucent liquids contained in bottles or other containers which are transparent or substantially transparent. .In this adaptation the device is used to make possible the rapid inspection of the contents of the containers and/or walls or surfaces of the containers to detect foreign substances in the liquid, turbidity of the liquid, lack of uniform mixture of the liquid or to detect cracks or other defects or flaws in the bottles, or to detect insufliciently cleaned bottles.

With the above purposes in view, and in order to produce an inspection device which functions more emciently than other known devices oi this class, it is one of the objects of this invention to produce an inspection device which will automatlcally produce images of the articles ofv ample size for the convenience of the inspector, and which will maintain the size of the image substantially constant from the time that'the article enters the enlarging field until the article leaves the enlarging iield. T

A further object of this invention is to produce a device which is non-glaring, which is easy on the eyes of the observer and which, accordingly, does not produce eye strain. i

A further object of this invention is to produce an inspecting device in which the observer may change his position to a substantial degree without seriously affecting the size or position of the enlarged images of the articles.

A further object of this invention is to produce an inspection device in which no high lights or other bright objects are reflected to confuse the observer andin which the reflection consists only of those articles which are being inspected and 5 Claims. (01. sit-14) the illuminated or other articles.

A further object of this invention is to produce an inspection device in which both sides of the article are visible from the usual position background for the of the observer, one side being visible in enlarged form and the other side appearing in its natural size.

A further object of this invention is to produce an inspection device provided with the various adjustments to enable the observer to regulate the size and location of the image to suit his convenience.

Further and more specific objects of this invention will become apparent from the following description and claims. This description sets forth in detail certain devices embodying this invention, such disclosed devices constituting, however, but'one of the forms in which the principles of this invention may be applied.

Referring to the annexed drawings:

Fig. 1 is a side elevation of my improved inspection device partly-broken away to show certain interior details, the conveyor with which this vations ofone detail of the mirror support ofthis inspection device.

Fig. 6 is a front elevation of this improved inspection device as it appears when looking in the direction indicated by the arrows 6, 8 in Fig. i.

Fig. 'l is an oblique view looking at this apparatus from a position to the right of and above the light casing this being one usualposition assumed by the observer when inspecting bottles, the mirror in this illustration showing the image seen by the observer underthese circumstances.

Referring to the annexed drawings, in which similar numerals indicate similar parts throughout the several views. this improved inspecting device comprises a supporting structure which may be of any preferred form but which is here shown as including a base I, in which is mounted a tubular standard 2, this standard being slidably mounted for vertical adjustment in the base and adapted to be fixed in any desired adjusted position by means of handscrews 3, l.

i A main frame 4, preferably formed by casting,

is mounted upon the upper end of the standard 2, this frame 4 being formed on its under side with a hollow socket 5 located substantially centrally on the casting and adapted to be fixed in v the standard by one or more hand screws 6.

This frame comprises a front portion 1 and a.

rear portion 8, the front portion being that section of the frame 4 nearest to the observer.

Intermediate the front and rear portions oi? the frame 4 isa support for the upper strand 9a of a conveyor. this support consisting, in the embodiment illustrated, of a pair of spaced channels l0, l0 running thru the inspection device. These channels may be supported on the frame 4 or they may be supported by any desired means entirely separate from this frame as is assumed in the disclosure in the drawings.

Disposed vertically above the channels l8, iii are a pair of relatively narrow guide rails l2, I2 supported upon the frame 4 by means of bars I3, I3 on angle brackets l4, l4 these guide rails being provided to prevent the bottles l5 or other articles mounted on the conveyor Go from shifting laterally on the conveyor and they are made relatively narrow in order that they may obstruct the view of the bottles as little as possible. The lower or return strand 8b of the conveyor is supported on an idler roller l8 disposed prefer ably vertically beneath the conveyor supports l0, l0 and located in a gap l'l formed in the frame 4.

This conveyor illustrated as consisting of upper strand 9a and lower strand '9b may be a traveling conveyor of any kind or any type of apparatus for moving the articles past the inspection device and, when in the form of a chain or belt this conveyor is usually endless. In this event, the return strand 8b may be located at any convenient position. The idler roller i8 is provided as being one convenient expedient to provide for the return passage of the lower or empty strand of the conveyor.

Mounted on the front portion 1 of the frame 4 is a casing or cabinet l8 enclosing a source of light preferably consisting of one or more electric lamps i9 mounted on a hinged wall 20 and located in that end of the cabinet farthest removed from the conveyor 9a. The side walls 2|, the upper and lower walls 22 and 23. respectively, of the cabinet as well as the door 28. are prefer-'- ably forrned of opaque maternal. The rear end of the casing, that is the end facing toward the conveyor 90, is closed by a plate of translucent material permitting the passage of light in diffused form such for instance as the frosted glass indicated at 24.

lamps is toward the path-above the conveyor thus permitting a greater diflusion of the light furnished by the lamps and making possible the use of a diffusing plate of a relatively large area.

The support for the casing "consists of a flangeconstr'tiletion 25 secured to'the' lower wall 23 of'the casing to which is attached 9.

rod or bar 28. This rod 26 is mounted in vertical sliding and rotatable engagement in an opening 21 formed in a boss 28 on the front portion the frame 4 and also with reference to the com veyor 9a andthat these elements are likewis'; rotatably mounted about a vertical axis. It follows therefore that the light from the diffusing platemay be directed at any angle with reference to the path of the conveyor in a horizontal plane and that the vertical location of these light rays may be varied within the limits of the adjustment.

Mou'nted on the rear portion 8 of the frame 6 and substantially juxtaposed to the casing I8 is a concave reflecting mirror 30, this mirror being a spherically concave mirror in the embodiment disclosed. The mirror 381s preferably rectangular in outline as shown and is-mounted in a rectangular frame 81 formed with a trunnion 32 at each side. Convenient means are provided in the frame for the replacement of the mirror if this is inadvertently damaged or broken. As shown in the enlarged views Figures 4 and 5, the trunnions 32 are each seated in a split bearing 38 at the top of standards 34. It will appear that the mirror 38 is thus tiltable about a horizontal axis coincident with the axis of the trunnions, this axis being normally substantially parallel with the path of the conveyor. Hand screws 86 engage the two parts of the split bearing whereby the trunnions 82 may be firmly gripped to hold the mirror in any desired adjusted position.

The standards 84 are supported in vertical openings 38 formed in the ends of a beam 31 pivoted substantially in the center upon a vertical stud 38 as shown in Figures 1 and 3. From this it will appear that the concave mirror 80 may be vertically adjusted to any desired position within the range of the construction and also that the mirror may be angularly adjusted about a vertical axis as may be desired. Hand screws 39 are provided to hold the standards 34 in the desired vertical position and a clamping nut 40 is provided to frictionally hold the beam 31 in the adjusted position against the top of the boss 4i inwhich the stud 38 is mounted.

The boss 4| is integrally formed with a supporting rod 42 extending forwardly from the boss, this rod being slidably and rotatably mounted in a horizontal opening 48 formed in the rear portion 8 of the frame 4 as clearly shown in Fig. 1. It will accordingly be evident that the mirror and frame may be moved or shifted in a direction toward or from the conveyor 841 by horizontally sliding the rod 42 in the opening 43. It will also appear that the entire mirror and frame may be rotated about a horizontal axis coincident with the axis of the opening 42 this axis being substantially at right angles to the plane of the path of the conveyor. A hand screw 44 is provided to hold the rod 42 in th desired position in the opening 42.

Operation The operation and use of this improved inspecting device is as follows:

The bottles I! or other articles to be inspected are placed upon the upper strand is of the 76 moving conveyor upon which they are moved past the light diffusing plate 24 and past the field of the concavemirror 30. The inspector preferably sits in front of the inspection device in such a position that his eyes are located somewhat above the tops of the bottles being inspected and preferably laterally of the light casing l8 so that neither the passing bottles nor the top of the light casing prevent the observer from obtaining a substantially complete view of the mirror. A satisfactory position for the eyes of the observer is to the right of and above the casing l8. The view obtained by the observer from the position indicated is substantially similar to that shown in Fig. '7.

As the bottles enter and traverse the fleld of the mirror, enlarged images of the bottles, as indicated at E5, are reflected to the eyes of the observer. The size of the images depends upon the proximity of the observer's eye tothe mirror and also upon the proximity of the face of the mirror to the passing bottles. For some purposes, such an enlarged image is satisfactory to disclose the undesirable defects to the observer with ordinary daylight or other room illumination. For purposes of satisfactory inspecting some classes of articles, however, particularly bottles containing partly or highly colored liquids, it is necessary to provide additional illumination upon the articles, this illumination being preferably located as shown in the drawings and comprising a source of light including a .light diffusing plate of glass or similar material. The positions of this light diffusing plate and the mirror are so adjusted with reference to the eye of the observer that he sees the image of the light diffusing area in the mirror, and, as the bottles pass the field of the mirror, they are not only magnified but illuminated by the soft light which is transmitted thru the bottles and thru the liquid contained in the bottles, thus making it relatively easy for the observer to detect not i only flaws, cracks, dirt or other defects in-the walls or on the surfaces of the bottles, but also to detect turbidity, lack of uniformity or foreign substances in the liquid. Any defective bottles are removed manually by the observer for correction or rejection and the perfect bottles continue on the conveyor to be labeled or packed, as will be understood. i

It will be noted that this inspection device makes it possible for the operatorto observe both sides of the articles to be inspected. The side of the. articles away from the observer is seen in the enlarged reflected images, and at the same time the side of the articles toward the observer is visible for direct inspection by the observer asthe articles approach or recede from the inspecting device.

This improved inspecting device automatically produces enlarged images of the articles to be inspected and maintains the size and nature of these images substantially constant from the time the article enters the reflecting field of the mirror until it leaves the field.

This device has the further advantage that the enlarged image, visible to the observer, is not materially changed in size, position or character if the observer changes his position any normal amount to suit his convenience or comfort, and

with this device it is therefore not necessary for the observer to remain rigidly in one position.

It is also important to note that the concave mirror reflects only the articles to be inspected and the diifused light area and certain other 'or suspended from the ceiling, as will be underadjacent parts of the device whose reflecting qualities can be controlled, and the mirror does not reflect any highlights or bright objects originating outside of the device, this device being non-glaring and easy on the eyes of the operator. 5

A further important advantage of this apparatus is the fact that it is not necessary for the observer to sit in a positionin which the direct head-on reflected rays from the diffusing plate strike his eyes at right angles, thus tiring his 10 I eyes; the observer may take a position in which he views the reflection of the diffused light area from a positionpff the line of direct reflection, whereby he does not receive the direct reflection of the difiused light area but receives the reflec- 15 tion at an acute angle. In other words, the observer does not find it necessary to view the reflection along the line, a,'b, Fig. 2, which indicates the path of the direct reflection of the center of the diffused light area; he mayview the 20 tions of the observer's eye.

Equivalent constructions It will be understood that various alterations, 30 modifications, and/or additions may be made in the apparatus shown without departing from the scope of this invention as defined by the appended claims.

For instance, while this inspection device is illustrated and described in its adaptation as a bottle inspecting device it will be understood that this device is not limited to the inspection of v bottles or other transparent or translucent containers or materials. This invention may with equal advantage be used for inspecting opaque articles to discover defects or undesirable conditions on the surfaces of such articles.

' It also follows thatany typeoi support or supports may be used for the several elements comr' prising this invention. All the elements may be 'mounted on one support or each'element maybe mounted on an individual support and any or all supports may be supported either on thefioor stood.

It will also be evident that opalescent glass, ground glass, ribbed glass, colored glass, cloth or other colored material may be used in place of frosted glass 24 as a light diffusing element.

Other conformations of enlarging mirrors in addition to the spherical shape described might be used; as an-example, for some purposes enlargement in one direction is desirable. in which event a concave cylindrical mirror is used. In some instances only a portion of the object re-. quires enlargement in which case a mirror of irregular shape is used. It will also be understood. that shapes of mirrors, approximating the spherical and/0r cylindrical may be used without departing from the scope of this invention.

In the broader aspects of this invention it is not essential that the articles inspected pass between the source. oi. light and the mirror, as the mirror produces very images of the objects passing on the conveyor when the source oi illumination and the mirror are on the same side of the conveyor. This'arrangement may advantageously be used for'inspecting opaque objects. 75

In some asp cts of this invention the source of light'associated with the device is not an indispensable element, as this inspection device produces very efllcient results for some types of inspection with ordinary room illumination.

Many other modifications of this invention and its application will naturally occur to those skilled in .this art, and the present disclosures should therefore be considered as typical only and I desire notto be limited to the exact construction shown and described.

What I claim is;

1. A device for inspecting successively a multiplicity of articles in motion including a supporting structure, a conveyor for moving the articles successively over a part of the supporting structure', a light source; comprising an opaque housing and containing a lamp, said housing being mounted on that side of the supporting structure at which an observer may be stationed and being adapted to project light across the conveyor and through the zone occupied by articles thereon, and a concave mirror mounted on the opposite side of the supporting structure arranged to receive light from the light source and reflect said light past a margin of the opaque housing of the light source.

2. A device for inspecting successively a multiplicity of articles in motion including a supporting structure, a conveyor for moving the articles successively over part oi the supporting structure, an opaque housing containing a light source mounted on that side or the supporting structure at which an observer may be stationed and adapted to project light'across the conveyor and through the zone occupied by articles thereon, and a concave mirror mounted on the opposite side oi the supporting structure and movable through a range of adjustment which includes a position making such angle with the line of the conveyor that light projected by the light source across the zone oi the conveyor between the light source and the mirror will be received by the mirror and reflected past a margin oi the housing.

3. A device for inspecting successively a multiplicity of articles in motion including a supporting structure. a conveyor for moving the articlessuccessively over part of the supporting structure, an opaque housing containing a light source mounted on that side of the supporting structure at which an observer may be stationed and adapted to proiect light across the conveyor and through the zone occupied by articles thereon,

and a concave mirror mounted on the opposite 4.. A device for inspecting successivelya multiplicity of articles in motion including a supporting structure, a conveyor for moving the articles successively over a part 0! the supportingstructure, an opaque housing containing a lamp mounted on that side of the supporting structure at which an observer may be stationed and being adapted to project light across the conveyor and through the zone occupied by articles thereon, and a concave mirror mounted on the opposite side of the supporting structure at such an angle to the line of the conveyor that light projected by the lamp across the zone of the conveyor between the lamp and the mirror will be received by the mirror and reflected past a margin oi the opaque housing.

5. A device for inspecting successively a multiplicity of articles in motion including a supporting structure, a conveyor for moving the articles successively over part oithe supporting structure, an opaque housing containing a lamp mounted on that side of the supporting structure at which an observer may be stationed and being adapted to project light across the conveyor and through the zone occupied by articles thereon, and a concave mirror mounted on the opposite side oi the supporting structure at such an angle to the line 0! the conveyor that light projected by the lamp across the zone of the conveyor between the lamp and the mirror will be received by the mirror and reflected past an upper portion of the margin of the opaque housing of the lamp, whereby the observer may see in the mirror, apparently above an article which has just passed into direct view oi theobserver from behind the opaque housing, a virtual image of a succeeding article which is at the moment between the lamp and the mirror and masked by the opaque housing from direct view by the observer.

GEORGE J. HEWLETT. 

